The present invention relates to a computer system with databases. More specifically, the present invention relates to the replication of databases in a computer system in which different types of database management systems (DBMS) are present.
In the past, corporate information systems comprised mainly of on-line transaction processing systems (OLTP systems) that primarily used mainframes. These are known as enterprise systems or management systems. However, in recent years OLTP systems by themselves could not provide efficient support for strategic decision making, and this has led to the introduction of data warehousing. In data warehousing, history information is extracted and accumulated over time from OLTP systems to allow efficient analysis of client trends and market trends. This type of system is also referred to as an integrated information system.
While conventional OLTP systems have been built primarily around mainframes, data warehouses and data marts are often built with open systems. Thus, platforms and performance requirements may vary, and the DBMS used in the OLTP system is often different from the DBMSs used in the data warehouses and data marts. Thus, in today's corporate information systems, different DBMSs are used together, and data must be extracted and updated between these databases.
However, analyzing client trends and markets brings the need for the most recent data that will allow the most appropriate services and products to be provided and will allow the most effective investment decisions. Furthermore, a composite analysis of different types of information is likely to allow more effective analysis. However, there is generally a trade-off between the amount of data to be extracted and the frequency at which data is to be extracted, and there is a limit to how much both can be increased. Without appropriate control over performance, optimal analysis cannot be provided.
What is really needed are techniques for combining databases, especially databases having heterogeneous formats, in a disk storage system.